No reverse lights + codes U170b & U0200

[Cycu]

Hi.
I have a Ram 1500 Sport 5.7L, 2013, 8-speed automatic.

I was outside the country for 10 months and the car hasn't been used most of that time.
Recently the passenger side door stopped working completely giving the code U0200. Turn light on side mirror is off, windows not working.
I was trying to troubleshoot where the problem comes from, checked the wirings and it started fully working somehow.
Today the same thing came back and I can't figure out where it comes from or how to fix that. Fuses looks good.

If it wasn't enough my reverse lights are completely gone with the code U170b.
I can't even light them up through OBD.
This code doesn't come up again after i deleted it in Alfa OBD and yet no reverse lights are present.

I would really appreciate your help

 

[MADDOG]

P0200: This code means that the Door Control Module B (DCM-B) and other control modules on the vehicle are not communicating with each other. The circuit most often used to communicate with is known as Controller Area Network bus communications, or simply put, CAN bus.

The Door Control Module B (DCM-B) is typically located behind the kick panel adjacent to the door in question. May also be mounted inside the door in question. It receives inputs from a variety of sensors, some hardwired directly to it, while most are sent over the bus communications system from the Powertrain Control Module (PCM).

Typically the causes for this code to set are:
Open in the CAN bus + or - circuit
Short to power or ground in either CAN bus circuit
No power or ground to DCM-B module
Rarely - faulty control module

U170B: Take a look at this table of possible U170B code faults Dot Report - U170B

 

[GeauxinUp]

Assuming you’ve load tested the battery, I’d suspect a critter chewed something up while it sat for so long

 

[RamDiver]

My primary concern after a truck isn't used for that time is the battery.

Once the power source for all the electronics is compromised, you can expect erratic DTCs and/or numerous functionality issues.

I would start with load testing the battery with a toaster-style battery load tester like this $18 unit from Harbour Freight. I realize you're located across the pond, but there are similar devices in your area.

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